The present invention generally relates to a helical scan type magnetic recording/reproducing apparatus for domestic use. More particulary, the invention concerns a magnetic recording/reproducing apparatus in which each of slant tracks formed on a magnetic tape is divided into a plurality of sub-tracks or areas in the longitudinal direction of the track, wherein audio signals having undergone a pulse code modulation (hereinafter referred to as PCM audio signal) are each recorded or reproduced on or from the sub-tracks (areas or channels) resulting from the division.
In general, the helical scan type magnetic video recording/reproducing apparatus (such as a VTR) for domestic use has a rotatable cylinder on which magnetic heads are mounted with an angular displacement of approximately 180.degree. C. therebetween. A magnetic tape is wound or wrapped at a slant around the periphery of the cylinder over an angular range of approximately 180.degree., whereby a video signal is recorded on the record track formed at a slant relative to the direction in which the magnetic tape is transported.
Recently, it has been proposed that the record track is divided in a plurality of sub-tracks or areas in the direction trackwise and that a PCM audio signal is recorded or reproduced on or from each of the areas resulting from the track division instead of the video signal.
More specifically, according to the proposed audio signal recording method, a single video track is divided into six sub-tracks or areas in the longitudinal direction of the track to thereby prepare first to sixth channels. For recording the signal on the first channel, a PCM audio signal is recorded only on the first channel while no recording is made on the second to sixth channels. This recording operation is performed sequentially on the adjacent tracks from one to another. Of course, for the recording of the second channel, only the sub-track or area corresponding to the second channel is subjected to the recording sequentially on the track basis (i.e. from track to track).
In this conjunction, it is noted that the magnetic video recording/reproducing apparatus includes an erasing head which has a width large enough to erase the record widthwise over the whole width of the magnetic tape. Consequently, when the video track is divided into six sub-tracks or areas for recording different PCM audio signals on the six corresponding channels, respectively, it is impossible to selectively erase only the desired channel for the purpose of recording again a new PCM audio signal thereon.